Galvanometer



(No Model.)

2 Shets-$heet 1. I. W..OHISHOLM.

GALv-ANOMETER.

No. 390,067. Patnted Sepia. 25, 1888.-

I Unire 'Srnrns Armer Fries..

ISAAC W'. C HISHOLM, F NEW (JONCGRDy Ol-llt'l.

eanvssomerefa.

Y. SPECIFICATIQN forming partei' llgetters Patent No. 390,067, dated September 25, 1888.4 v

Zh all whom) t mwyroncern.- h

Be. it known that I, Istrie CnisHoLi/I, a citizen of the United States of America, residing at New Concord, inthe county of MuskingumandI State of Ohio, have invented certain new and useful Improvements in Galvanome- 'l ters; land I do hereby declare the follcwing to be a full, clear, andexact description f the invention, such 'as will enable others skilled ro in the art to which it appertains to make and use the saine, reference being had to the accennpanying drawings, and to letters or figures of i reference marked thereon, which form a part of this specification. i5 My invention relates to certain new and useful improvements in galvanometers; and,` it consists in the use of a speciallyeonstructed galvauoineter,in combination with two detachable electrode -arms respectively carrying 2o platesot' metal of dilerent electrical inherent properties, preferably zinc and copper, to be placed within the mouth ,and acted'upon by the acids and alkalies of the 4human saliva, thereby causing a molecular excitation of said z5 plates and a generation ofan electric current, the tension of which will be registered and in:

dicated by the needle of` the galvanometer moving relatively in connection with a pr`edetermined scale. f The priinary object of iiy invention is to provide an apparatus for ascertaining the intensity of an electric current irrt-he human body, or, in other words, what tension of current the acidsand alkalies carried by the human saliva will generate 'in different individuals. The secondary object of inyiuventiou is to provide an apparatus for the purpose set forth, wherein a galvanoineter of preferred form of construction is used in' combination with d- 4o tachable electrode-arms carrying flat plates of metal', preferably of zinc and copper, at their outer ends, having electrical connectionswith, the galvanometer at their inner ends, whereby plates of various sizes and arms of dilierent lengths may be substituted at the will of the operator for dili'erent purposes.

In the accompanying drawings Ibavc illustrated my improved form of construction, the ,similar parts thereof uniformly lettered, and 5o are as'follows: l'

Figure l'is a .perspective view of my iinprovement. Fig. 2 is a. similar view of the -iiicoils and connections of thegalvanoineter,.th casing being removed. FigLlS is a sectional view through the coil.' Fig, 4 is. a,longitudi 55 lnal vertical sectional view o'lllone of the defthe same. This basehas hardrubberblocks c rigidly secured thereto, thronglrwhleh screwspassaud into vertically-arranged hardy rubber rectangular side pieces', C, havingcenti'al openings, c?, which serve as supports for 65v the hard-rubber transverse bars C', around which the'ne insulatedwire of the coil Die! wound. The terminals of the coil extend' through the side pieces, (l, and are attachedto the bases of the bindingposts B; i 7o Hardrubber' vertical supports dare secured te-shebase A@ and forni. asnppeiztinglconnec--` tion for the rubber top plate, E. inthe top' plate and base a circular. metallic band, -D, is located, which completely covers the coil and protectsthe same from injury. i

The top plate, E, is provided adjacent to its center with perforations e, within which lie metallic projections e', formed' with anietallic plate, f which supports the pivot-pin of the 8c needle g. These projections on the plate f are internally screw-threaded to secure the same t0 the plate E by suitable screws and washers. The pocket F, within which is placed the mag- .nctic needle g, is provided with an inwardlyprojectinglafnnular scale-plate, h.,and thencedlegregistcrs therewith in the usual manner. G indicatesthe cords inclosing the electrical conductors, attached at their inner ends to the bindingposts B, and at their outer ends 9o carrying metalliccoutacts y', of ordinary form .of construction. t.

Electrode-arms II Il are provided and have sockets h formed on their inner en ds, with which setscrews S engage to dctachably secure 95 the said contacts to the arms g', and conse qnently to a gallvanoineter. .lhe sockets h' are connected to oute` metallic disks i and i', by lm cans ol' wires s, wh ich are screw threaded and secu red to the said sockets, as shown ,`and IOO over said wires s, between the sockets h and l, the said plates I I', a hard-rubber cylinder, la, is niounted,to be held by the lingers and thereby forin a nou-conducting support. When the plates I t are within the mouth, the lips will bear upon said cylinders l, for purposes which wiil be readily understood. One of said disk? plates is preferably made of zinc and the other ofcopper, silver, or nickel, as may be desired. The arms are made detachable for the purpose of making the device convenient to substitute various sizes of electrode-arms and wires s, carrying different forms and kinds 0f metallic disks'.

` Having .thus described my invention, Vi claim- 1. In a galvanometcr, the combination, subv stautially as described, ofthe base A, having the uprights b and bindingposts 11, secured thereto, the blocks c, secured to the said base, the vertically-disposed side pieces, (I, secured te and supported by said blacks q, the transverse bars C', around which the wire 'of the coil is wound, supported by said side pieces, C, adjacent tothe ends thereof, said parts, with the exception ofthe bindingposts B, all being constructed of a non-conducting material, preferably hard rubber, and the4 casi ng, nee' die, and electrical connections, substantially as described. t

2. The combination, with thegalvanometer herein described, ofthe electrodearms having sockets h', set-screws passing,r into said sockets for detachably securing said arms to the metallic contacts on the ends of the terminals of the galvanomcter, the said sockets having wires s, detachably connecting the same with dat disks I I', of metals having diferentinherent electrical properties, and a hardrubber cylinder, h, placed over said wires .s' between the sockets h' and the outer disk'plates, I l', substantially as described.

3. The combination, with the base A, ofthe block c and the vertically-arranged oppositel ly-situated rectangular side pieces, C, inclosing and securely supporting the transverse bars C', around which and` between the side pieces, (.1, the insulated wire forming the coil l) is wound, the said parts A, c, C, and C' all being constructed of hard rubber, substantially as described.

In testimony whereoll. affix my signature in presence of two witnesses.

ISAAC W. GHISHOL'M.

Witnesses:

`JAMES D. ARNsroicnn,

Jas. II. Amin. 

